How to grind the Festfloor microcement? 
Check if you are doing it right

Grinding microcement – nothing complicated, but it is worth writing a few words about it. When to grind the microcement? Can the grinding step be skipped? What tools to use? Let’s clarify.

Grinding microcement with an eccentric sander connected to a vacuum cleaner.

01

After what time should I grind the Festfloor microcement?

Each of the microcement layers should be grinded to obtain a smooth surface. The more precisely we apply the microcement, the less work it will be for grinding. FESTFLOOR microcement (both Festfloor Life  and Festfloor Go!) is best sanded after about 4 hours. This is the optimal time, because the material will then set and will be dry, and at the same time will not be too hard. We do not recommend sanding to the next day, when microcement is fully cured. This can finish you and your grinder off!

02

Can I skip the grinding step?

We always recommend grinding the surface. If you do not grind it, it will be more difficult to apply the second layer, because the float will jump over the uneven material. Additionally, keeping the surface clean later may be more difficult, because the mop will not slide well, and dirt particles can penetrate the material.

03

How to grind the Festfloor microcement?

Single-disc grinders (sanding machines) are used for grinding microcement. The first layer is sanded with  60-120 grit sandpaper and the second layer with  80-grit sandpaper or more (depending on the desired effect). Hard-to-reach places (corners, along walls, etc.) should be sanded with manual eccentric grinders with triangular base plate. It is also good to connect a good quality vacuum cleaner to the grinder, which will collect all the dust.
These grinders are easily available and relatively cheap, they can also be rented from construction equipment rentals, so when making microcement on his own, the investor does not have to spend too much on equipment.
On the other hand, professional contractors who make large floor areas, eagerly invest in professional floor grinders, thanks to which the work goes much faster. Grinders should be purchased with pads and sanding discs.

04

What grinding equipment should I use? What do experienced contractors recommend?

Thomas:
"The first steps were made by the Graphite eccentric sander, where I could not connect the hose to the vacuum cleaner without alterations. I still have it today. The best buy – Mirka Deros – Mercedes doesn’t get any better. I still have Metabo in emergency. Currently, the corners are polished by a borrowed Festool DTS 400, and it performs very well, but for comparison, I will also borrow the Rotex 90 to have an accurate overview before buying. The biggest disappointment is the new Festool vacuum cleaner, equipment in this class is sold even without cleaning nozzles and with a 3.5 m hose …"

Peter:
"We grind large surfaces with the Menzer 406 orbital floor sander with an additional load and a vacuum cleaner system. We fly small surfaces and corners with a Metabo 150 mm eccentric griner and the Festool DTS. If someone says that Mirka is the best, he has not yet tried the Flex ORE 5-150 EC eccentric sander. Much cheaper and much less fallible. Fully recommended!"

Boris:
"I also started on a Metaboo orbital sander and the cheapest vacuum cleaner from the same company. The filter is clogged up every 10 minutes, so I advise against buying the cheapest equipment. I think that the vacuum cleaner is the basis and Festool works for me. I am currently working on a Festool eccentric  sander which is very light. As a result, sanding is more pleasant and faster. The only drawback is the rapidly falling plates. I use the Numatic 1400W grinder for larger surfaces. I make meters of floors and I can recommend it. You can buy a used one in good condition for PLN 2,000. For this I use various pads and sanding pads. The Fein multitool is also a nice and handy power tool. It can sand corners, cut expansion joints and help with many other works that often occur at construction sites. For expansion joints, of course, the Festool AG125."

Gregory:
"For large surfaces we use Menzer 406, and the small ones with Flex Ore 5, Cat, JCB, and others. The best vacuum cleaners are Starmixy and Flexy 44."

Grinding microcement with a floor grinder (single disc)